Malicious Google Ad --> Fake Notepad++ Page --> Aurora Stealer malware

Published: 2023-01-18
Last Updated: 2023-01-18 07:31:54 UTC
by Brad Duncan (Version: 1)
0 comment(s)

Introduction

Google ads are a common vector for malware distribution.  Do a Google search for any popular free software download.  Review any search results marked "Ad" or "Sponsored," then check the link to see if anything is unusual.

I've already written two diaries and authored various tweets about this type of activity:

Others have also reported his activity.  Recent posts include:

One example of free software routinely spoofed for Google ads is Notepad++.  Almost without fail, I can find a fake webpage for Notepad++ every day through Google ads.  For today's diary, I found a Google ad for a malicious site at notopod-plos-plus[.]com.


Shown above:  Google ad for fake Notepad++ site.  Misspelled "Notepad" as "Notepade" in the ad.

These fake sites copy pages from the real software sites and have links to download the malware.


Shown above:  Downloading malware form the fake Notepad++ page.

The URL to download malware was notopod-plos-plus[.]com/bsdf/file.php which redirected to another URL hosting the malware.  I found the redirect by using a URL shortner revealer.  In this case, I used expandurl.net and found the malware hosted at hxxps://obsqroject[.]com/npp.8.4.8.Installer.x64.exe.  Note the "q" in "obsqroject" in the malware download URL.  The malware is 'hosted on a server impersonating the legitimate site obsproject.com.


Shown above:  Using a tool that reveals locations of shortened URLs to find a redirect for our malware.

The downloaded malware was detected by Microsoft Defender as an unrecognized app, so I had some extra clicks to run it.


Shown above:  Windows Defender doesn't like this type of downloaded EXE file.

Post-infection traffic caused by this malware went to a server at 79.137.133[.]225 over TCP port 8081.


Shown above:  Post-infection traffic shown in Wireshark.

Post-infection traffic consists of plain text.  Text sent by the server to the infected Windows host was WORK and Accept and Thanks. Data sent by the infected Windows host to the server looks like Base64 text.


Shown above:  Start of TCP stream for the post-infection traffic.


Shown above:  End of TCP stream for the post-infection traffic.

Note the server sent WORK once, Accept multiple times and Thanks twice.


Shown above:  Text sent from the server to the infected Windows host.

This post infection traffic follows patterns seen with previous examples of Aurora Stealer malware.

Indicators of Compromise

Google ad traffic to fake Notepad++ site:

  • hxxps://www.googleadservices[.]com/pagead/aclk?sa=L&ai=DChcSEwiNnNGbq9D8AhUOFdQBHYudC80YABAAGgJvYQ&ohost=www.google.com&cid=CAASJORocbWbOK8xihLbtr-uk4JIaGPISKgFmjK_urkXpVpd9puZOQ&sig=AOD64_3UiS622EDVVxZE1kULfyg7CYIZgA&q&adurl&ved=2ahUKEwik1sqbq9D8AhXJmGoFHamhBjM4MhDRDHoECAEQAQ
  • hxxps://notopod-plos-plus[.]com/?gclid=EAIaIQobChMIjZzRm6vQ_AIVDhXUAR2LnQvNEAMYASAAEgKemfD_BwE

Traffic to download the malware:

  • hxxps://notopod-plos-plus[.]com/bsdf/file.php
  • hxxps://obsqroject[.]com/npp.8.4.8.Installer.x64.exe

Aurora Stealer post-infection traffic:

  • tcp://79.137.133[.]225:8081

Downloaded Aurora Stealer malware sample available at:

Sandbox analysis of the Aurora Stealer malware:

Final Words

Criminal groups frequently use Google ads to distribute malware.  These ads frequently lead to fake sites impersonating web pages for legitimate software.  In some cases, these malicious files install a copy of the legitimate software and include malware in the background.  In other cases like this one, the files just run or install malware.

In most cases, Microsoft Defender warns victims these files are potentially dangerous.  Unfortunately, many people click past these warnings and infect their computers.

How can we best prevent these infections?  My advice is to follow best security practices and avoid ads when searching for free software downloads on Google.

----
Brad Duncan
brad [at] malware-traffic-analysis.net

Keywords:
0 comment(s)
ISC Stormcast For Wednesday, January 18th, 2023 https://isc.sans.edu/podcastdetail.html?id=8330

Comments

cwqwqwq
eweew<a href="https://www.seocheckin.com/edu-sites-list/">mashood</a>
WQwqwqwq[url=https://www.seocheckin.com/edu-sites-list/]mashood[/url]
dwqqqwqwq mashood
[https://isc.sans.edu/diary.html](https://isc.sans.edu/diary.html)
[https://isc.sans.edu/diary.html | https://isc.sans.edu/diary.html]
What's this all about ..?
password reveal .
<a hreaf="https://technolytical.com/">the social network</a> is described as follows because they respect your privacy and keep your data secure:

<a hreaf="https://technolytical.com/">the social network</a> is described as follows because they respect your privacy and keep your data secure. The social networks are not interested in collecting data about you. They don't care about what you're doing, or what you like. They don't want to know who you talk to, or where you go.

<a hreaf="https://technolytical.com/">the social network</a> is not interested in collecting data about you. They don't care about what you're doing, or what you like. They don't want to know who you talk to, or where you go. The social networks only collect the minimum amount of information required for the service that they provide. Your personal information is kept private, and is never shared with other companies without your permission
https://thehomestore.com.pk/

Diary Archives